This invention relates to ion sources and, more particularly, to a method and apparatus for rejuvenating ion sources.
One of the problems encountered in many electron bombardment or chemical ionization type ion sources that are often used with mass spectrometers is that the performance deteriorates with use. This problem typically arises because of the buildup of electrically insulating deposits within the ionizing chamber itself due to reactions between the charged particles and other materials in the chamber. For example, many samples that are analyzed can themselves cause such insulating coating.
These insulating coatings are a problem because they tend to mask the operation of the source electrodes and thereby degrade the performance of the ion source. The problem is readily corrected by shutting off the mass spectrometer and disassembling and cleaning the entire ion source. Unfortunately, this can be unduly time consuming.
A similar problem arises in the mass analyzer portion of a mass spectrometer since the deflecting electrodes, quadrupole electrodes and the like can also become coated with an undesired electrically insulating type coating. When such a coating occurs, the electric field required of such plates becomes distorted and performance is degraded.
Accordingly, it is an object of this invention to provide an improved method for rejuvenating ion sources.
A further object of this invention is to provide an improved apparatus for rejuvenating ion sources.